Documentation

Mathlib.Algebra.Homology.Localization

The category of homological complexes up to quasi-isomorphisms

Given a category C with homology and any complex shape c, we define the category HomologicalComplexUpToQuasiIso C c which is the localized category of HomologicalComplex C c with respect to quasi-isomorphisms. When C is abelian, this will be the derived category of C in the particular case of the complex shape ComplexShape.up.

Under suitable assumptions on c (e.g. chain complexes, or cochain complexes indexed by ), we shall show that HomologicalComplexUpToQuasiIso C c is also the localized category of HomotopyCategory C c with respect to the class of quasi-isomorphisms.

@[reducible, inline]

The category of homological complexes up to quasi-isomorphisms.

Equations
Instances For

    The condition on a complex shape c saying that homotopic maps become equal in the localized category with respect to quasi-isomorphisms.

    Instances
      theorem HomologicalComplexUpToQuasiIso.Q_map_eq_of_homotopy {C : Type u_1} [CategoryTheory.Category.{u_3, u_1} C] {ι : Type u_2} {c : ComplexShape ι} [CategoryTheory.Preadditive C] [CategoryTheory.CategoryWithHomology C] [(HomologicalComplex.quasiIso C c).HasLocalization] [c.QFactorsThroughHomotopy C] {K : HomologicalComplex C c} {L : HomologicalComplex C c} {f : K L} {g : K L} (h : Homotopy f g) :
      HomologicalComplexUpToQuasiIso.Q.map f = HomologicalComplexUpToQuasiIso.Q.map g

      The functor HomotopyCategory C c ⥤ HomologicalComplexUpToQuasiIso C c from the homotopy category to the localized category with respect to quasi-isomorphisms.

      Equations
      Instances For
        def HomologicalComplexUpToQuasiIso.quotientCompQhIso (C : Type u_1) [CategoryTheory.Category.{u_3, u_1} C] {ι : Type u_2} (c : ComplexShape ι) [CategoryTheory.Preadditive C] [CategoryTheory.CategoryWithHomology C] [(HomologicalComplex.quasiIso C c).HasLocalization] [c.QFactorsThroughHomotopy C] :
        (HomotopyCategory.quotient C c).comp HomologicalComplexUpToQuasiIso.Qh HomologicalComplexUpToQuasiIso.Q

        The canonical isomorphism HomotopyCategory.quotient C c ⋙ QhQ.

        Equations
        Instances For
          theorem HomologicalComplexUpToQuasiIso.Qh_inverts_quasiIso (C : Type u_1) [CategoryTheory.Category.{u_3, u_1} C] {ι : Type u_2} (c : ComplexShape ι) [CategoryTheory.Preadditive C] [CategoryTheory.CategoryWithHomology C] [(HomologicalComplex.quasiIso C c).HasLocalization] [c.QFactorsThroughHomotopy C] :
          (HomotopyCategory.quasiIso C c).IsInvertedBy HomologicalComplexUpToQuasiIso.Qh
          noncomputable def HomologicalComplexUpToQuasiIso.homologyFunctorFactorsh (C : Type u_1) [CategoryTheory.Category.{u_3, u_1} C] {ι : Type u_2} (c : ComplexShape ι) [CategoryTheory.Preadditive C] [CategoryTheory.CategoryWithHomology C] [(HomologicalComplex.quasiIso C c).HasLocalization] [c.QFactorsThroughHomotopy C] (i : ι) :
          HomologicalComplexUpToQuasiIso.Qh.comp (HomologicalComplexUpToQuasiIso.homologyFunctor C c i) HomotopyCategory.homologyFunctor C c i

          The homology functor on HomologicalComplexUpToQuasiIso C c is induced by the homology functor on HomotopyCategory C c.

          Equations
          • One or more equations did not get rendered due to their size.
          Instances For

            The category HomologicalComplexUpToQuasiIso C c which was defined as a localization of HomologicalComplex C c with respect to quasi-isomorphisms also identify to a localization of the homotopy category with respect ot quasi-isomorphisms.

            Equations
            • =

            The homotopy category satisfies the universal property of the localized category with respect to homotopy equivalences.

            Equations
            • One or more equations did not get rendered due to their size.
            Instances For